A large organisation of cancer doctors has issued a call to action to minimise alcohol consumption.
With a newly released position paper, the American Society of Clinical Oncology (ASCO) hopes to draw attention to the strong links between drinking alcohol and risks for several types of cancer.
"People are not aware of this," said Susan Gapstur, a vice-president of the American Cancer Society who was not involved with the position statement.
In a phone interview, Gapstur stressed that people living with cancer remain at risk for other cancers so it's important that they realise alcohol's role in cancer recurrence, too.
The call to action from ASCO follows a survey the group commissioned, which found that 70 per cent of Americans do not recognise drinking alcohol as a risk factor for cancer. In fact, alcohol consumption is known to increase the risk of several cancers, including head and neck, esophageal, liver, colorectal and female breast cancers.
Alcohol is classified as a carcinogen by the International Agency for Cancer Research. Approximately 3.5 per cent of all cancer deaths in the US - about 19,500 deaths - are alcohol-related, according to the US Centres for Disease Control and Prevention.
The ASCO statement, published in the Journal of Clinical Oncology, cautions that while the greatest risks are seen with heavy long-term use, even low alcohol consumption (defined as less than one drink per day) or moderate consumption (up to two drinks per day for men, and one drink per day for women because they absorb and metabolize it differently) can increase cancer risk.
Among women, light drinkers have a four per cent increased risk of breast cancer, while moderate drinkers have a 23 per cent increased risk of the disease. Heavy drinkers who consume more than eight drinks a day have a 63 per cent increased risk of female breast cancer because alcohol increases levels of the female sex hormone estrogen.
Dr. Noelle LoConte, a member of ASCO's prevention committee who is the lead author of the position paper, told Reuters Health that "pink washing," or exploiting the colour pink to show a commitment to finding a cure for breast cancer, leads people to buy pink bottles of liquor during breast cancer awareness month. They think they're helping to fight breast cancer, but nothing could be farther from the truth, she said.
Heavy drinkers of both genders increase their risk of head and neck and oral cancers by more than 500 per cent because tissues come into direct contact with alcohol carcinogens.
ASCO also notes that alcohol can worsen the impact of smoking. In addition, alcohol abuse can complicate outcomes among patients with cancer by contributing to prolonged recovery, longer hospitalizations and increased surgical procedures.
All forms of alcohol, whether beer, wine, champagne or shots, cause the same cancer risk.
"Alcohol consumption is one of the most difficult dietary factors to accurately ascertain. Most people don't know how much they've drunk (in terms of ounces), or how much alcohol is in what they drink. And most don't accurately recall how often they drink," Dr. Anne McTiernan, a cancer prevention researcher at the Fred Hutchinson Cancer Research Center in Seattle, told Reuters Health by email. McTiernan is also on the advisory panel that oversees the work of the World Cancer Research Fund.
In the US, 14 grams (0.6 ounces) of pure alcohol is found in 12 ounces of beer, 8 ounces of malt liquor, 5 ounces of red or white wine and 1.5 ounces or a "shot" of 80-proof liquor.
LoConte told Reuters Health by phone she hopes oncologists can be a "loud voice for policy change."
Preventing cancer is as important as treating it, she said, adding, "We hope that this paper makes a splash with other physicians so they can get alcohol prevention on their radar, too."